[physfs] LZMA decoding

> I dug the mail I had sent to you (Ryan) a while ago with an attempt of
> diagnose. I can send it again (on or off-list), if it can help. I
> reverted again to ZIP, for the moment, and all goes well since then.
Part of the problem is that the current LZMA support can't open more
than one file at a time. The LZMA SDK has some other intractable issues
with their C code, so I'm planning to replace the decompression code
with XZ Util's liblzma at some point, and just parse the 7zip archives
directly.
(but in case this is a simple fix for now, yes, please resend me the
mail off-list. Thanks!)
--ryan.